The table below records the intermediate steps that go into producing a cell phone and the value added at each step. For example, company A produces the outer case and keyboard, and sells it to company B for $$6\mathrm{.}00,$ who installs the internal hardware, adding $$12\mathrm{.}00$ in value.

$\backslash$table$[[$Intermediate steps to produce a cell phone$],[$Company$,$Steps,Value added at each step$],[$A$,$Assemble outer case and keyboard,$$6\mathrm{.}00$